The sodium glucose co-transporter 2 (SGLT2) is a transporter that reabsorbs glucose from the renal filtrate and prevents the loss of glucose in the urine. Because competitive inhibitors of SGLT2 cause the renal excretion of glucose, they may be used to normalize high blood glucose levels associated with diseases such as diabetes. Handlon, A. L., Expert Opin. Ther. Patents 15(11):1531-1540 (2005).
A number of SGLT2 inhibitors have been disclosed. See, e.g., Handlon, supra; U.S. Pat. No. 6,515,117; U.S. patent application publication nos. US 2006/0035841, US 2004/0138439. At least one inhibitor is in clinical development as a treatment for Type 2 diabetes mellitus. See, e.g., Komoroski, B., et al., “Dapagliflozin (BMS-512148), a Selective Inhibitor of the Sodium-Glucose Uptake Transporter 2 (SGLT2), Reduces Fasting Serum Glucose and Glucose Excursion in Type 2 Diabetes Mellitus Patients Over 14 Days” American Diabetes Assn. 67th Scientific Sessions, Abstract 0188-OR (2007).
The first known SGLT2 inhibitor was the natural product phlorizin (glucose, 1-[2-(β-D-glucopyranosyloxy)-4,6-dihydroxyphenyl]-3-(4-hydroxyphenyl)-1-propanone), and “all subsequent SGLT2 inhibitors have been glycosides derived from its structure.” Handlon, supra, at 1533. Phlorizin consists of a glucose moiety and two hydroxylated aromatic rings joined by a propanone spacer. Ehrenkranz, J. R. L., et al., Diabetes Metab. Res. Rev. 21:31-38 (2005). A review of the patent literature does not reveal any synthetic SGLT2 inhibitors that do not contain a glucoside moiety or a derivative thereof. Handlon, supra. In fact, “because of the relative uniformity of the glycosides in the SGLT2 patent literature, it has become increasingly difficult for potential drug inventors to find unexplored chemical space.” Id. at 1537. But attempts are still being made. See, e.g., U.S. patent application Ser. No. 11/168,905 to Eckhardt et al., entitled “D-Xylopyranosyl-Substituted Phenyl Derivatives, Medicaments Containing Such Compounds, Their Use and Process for Their Manufacture;” Ser. No. 11/182,986 to Eckhardt et al., entitled “Methylidene-D-Xylopyranosyl- and Oxo-D-Xylopyranosyl-Substituted Phenyl Derivatives, Medicaments Containing Such Compounds, Their Use and Process for Their Manufacture;” and Ser. No. 11/199,962 to Eckhardt et al., entitled “D-Xylopyranosyl-Phenyl-Substituted Cycles, Medicaments Containing Such Compounds, Their Use and Process for Their Manufacture.”